1. Field of the Invention
The invention relates to an energy-saving lamp, and more particularly to an energy-saving lamp with high-power spiral energy-saving light tube.
2. Description of the Related Art
Energy-saving lamps, with multiple types and advantages such as high luminous efficiency, long service life, environmental friendliness, good color, and compact structure, are increasingly popular by consumers. Spiral energy-saving lamps, particularly high-power spiral energy-saving lamps, are a common type. Due to advantages of high efficiency and energy-saving, they are widely used for indoor or outdoor lighting. Conventional energy-saving lamps include a lamp holder, an upper cover, a lower cover, a ballast, and an energy-saving light tube. The ballast is disposed inside the upper cover and the energy-saving light tube is fixedly connected to the lower cover. The energy-saving light tube is generally double spiral and has high power which is achieved by extending the length thereof. However, the longer the light tube, the higher the tube voltage. Too much high tube voltage causes the drive match between the ballast and the light tube to be unreliable. Second, to produce a high-power double spiral energy-saving light tube, long glass tubes are required and need to be curved in large scale by heating. Thus, the production process is very difficult and hardly suitable for mass production. In addition, the temperature of the tube wall of the high-power double spiral energy-saving light tube is very high, if a cold end is provided by conventional methods, for example, protruding from the top of the tube, the temperature of the cold end is difficult to control, which will greatly weaken the luminous efficiency.